Spin-on antireflective coating for integration of patternable dielectric materials and interconnect structures

• US 7,709,370 B2
• Filed: 09/20/2007
• Issued: 05/04/2010
• Est. Priority Date: 09/20/2007
• Status: Expired due to Fees

• Current Assignee: Globalfoundries US Incorporated (GlobalFoundries, Inc.)
• Original Assignee: International Business Machines Corporation
• Inventors: Brock, Phillip J., Lin, Qinghuang, Purushothaman, Sampath, Sooriyakumaran, Ratnam, Davis, Blake W., Allen, Robert D., Nelson, Alshakim, Huang, Wu-Song S.
• Primary Examiner(s): HO, TU TU V
• Application Number:
  US11/858,615
• Publication Number:
  US 20090081418A1
• Time in Patent Office: 957 Days
• Field of Search: 438/622, 438/736, 438/740, 257/758, 257/E23.145, 257/E21.575
• US Class Current: 438/622
• CPC Class Codes: H01L 21/02126 the material containing Si, O, and at least one of H, N, C, F, or other non-metal elements, e.g. SiOC, SiOC:H or SiONC
• CPC Class Codes: H01L 21/02137 the material comprising alkyl silsesquioxane, e.g. MSQ
• CPC Class Codes: H01L 21/02282 liquid deposition, e.g. spin-coating, sol-gel techniques, spray coating
• CPC Class Codes: H01L 21/02304 formation of intermediate layers, e.g. buffer layers, layers to improve adhesion, lattice match or diffusion barriers
• CPC Class Codes: H01L 21/02348 treatment by exposure to UV light
• CPC Class Codes: H01L 21/0276 using an anti-reflective coating anti-reflective coating for lithography in general G03F7/09
• CPC Class Codes: H01L 21/3122 layers comprising polysiloxane compounds
• CPC Class Codes: H01L 21/76802 by forming openings in dielectrics
• CPC Class Codes: H01L 21/76808 involving intermediate temporary filling with material
• CPC Class Codes: H01L 21/76835 Combinations of two or more different dielectric layers having a low dielectric constant H01L21/76832 takes precedence
• CPC Class Codes: H01L 23/5329 Insulating materials
• CPC Class Codes: H01L 23/53295 Stacked insulating layers
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/12044 OLED
• CPC Class Codes: Y10T 428/24802 Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]

Abstract

The present invention provides a method of fabricating an interconnect structure in which a patternable low-k material replaces the need for utilizing a separate photoresist and a dielectric material. Specifically, this invention relates to a simplified method of fabricating single-damascene and dual-damascene low-k interconnect structures with at least one patternable low-k dielectric and at least one inorganic antireflective coating. In general terms, a method is provided that includes providing at least one patternable low-k material on a surface of an inorganic antireflective coating that is located atop a substrate. The inorganic ARC is liquid deposited and comprises a polymer that has at least one monomer unit comprising the formula M-R¹ wherein M is at least one of Si, Ge, B, Sn, Fe, Ta, Ti, Ni, Hf and La and R¹ is a chromophore. At least one interconnect pattern is formed within the at least one patternable low-k material and thereafter the at least one patternable low-k material is cured. The inventive method can be used to form dual-damascene interconnect structures as well as single-damascene interconnect structures.

Claims

1. A method of fabricating an interconnect structure comprising:

providing at least one patternable low-k material on a surface of an inorganic antireflective coating (ARC) that is located atop a substrate, said inorganic antireflective coating is liquid deposited and comprises a polymer that has at least one monomer unit comprising the formula M-R¹ wherein M is at least one of Si, Ge, B, Sn, Fe, Ta, Ti, Ni, Hf and La and R¹ is a chromophore;

forming at least one interconnect pattern within said at least one patternable low-k material, said at least one interconnect pattern is formed without utilizing a separate photoresist material; and

curing said at least one patternable low-k material and the inorganic ARC into materials having a dielectric constant of not more than 4.3 and 7.0, respectively.

2. The method of claim 1 wherein said inorganic antireflective coating further includes at least one second monomer unit, said at least one second monomer unit has the formula M′

-R², wherein M′

is at least one of Si, Ge, B, Sn, Fe, Ta, Ti, Ni, Hf and La and R² is a cross-linking agent.

3. The method of claim 1 further comprising at least one additional component, including a separate crosslinker, an acid generator or a solvent.

4. The method of claim 1 wherein said at least one patternable low-k material comprises a functionalized polymer having one or more irradiation/acid-sensitive imageable groups.

5. The method of claim 4 wherein said functionalized polymer comprises a polymer of a hydrocarbon, a fluorinated hydrocarbon, a siloxane, a silane, a carbosilane, an oxycarbosilane, an organosilicate or a silsesquioxane.

6. The method of claim 1 wherein said curing comprises a thermal cure, an electron beam cure, an UV cure, an ion beam cure, a plasma cure, a microwave cure or any combination thereof.

7. The method of claim 1 further comprising forming a conductive material within said at least one interconnect pattern.

8. A method of fabricating a dual-damascene interconnect structure comprising:

providing a first patternable low-k material on a surface of an inorganic antireflective coating (ARC) that is located atop a substrate, said inorganic antireflective coating is liquid deposited and comprises a polymer that has at least one monomer unit comprising the formula M-R¹ wherein M is at least one of Si, Ge, B, Sn, Fe, Ta, Ti, Ni, Hf and La and R¹ is a chromophore;

forming first interconnect patterns within the patternable low-k material without a separate photoresist material;

providing a second patternable low-k material on top of the first patternable low-k material including said first interconnect patterns;

forming second interconnect patterns within said second patternable low-k material without a separate photoresist material; and

curing at least said second patternable low-k material and the inorganic ARC into materials having a dielectric constant of not more than 4.3 and 7.0, respectively.

9. The method of claim 8 wherein said inorganic antireflective coating further includes at least one second monomer unit, said at least one second monomer unit has the formula M′

-R², wherein M′

is at least one of Si, Ge, B, Sn, Fe, Ta, Ti, Ni, Hf and La and R² is a cross-linking agent.

10. The method of claim 8 further comprising at least one additional component, including a separate crosslinker, an acid generator or a solvent.

11. The method of claim 8 wherein said first and second patternable low-k materials are the same or different and comprise functionalized polymers having one or more irradiation/acid-sensitive imageable groups.

12. The method of claim 11 wherein said functionalized polymers comprise polymers of hydrocarbons, fluorinated hydrocarbons, siloxanes, silanes, carbosilanes, oxycarbosilanes, organosilicates or silsesquioxanes.

13. The method of claim 8 wherein said curing at least said second patternable low-k material comprises a thermal cure, an electron beam cure, an UV cure, an ion beam cure, a plasma cure a microwave cure or any combination thereof.